\version "2.18.2"

#(define-markup-command (harm-arrow layout props 
	largoflechax xceroadd segmentadox rom) 
	(number? number? boolean? markup?)
  "Draw a down curved arrow."
  (interpret-markup layout props
    #{\markup \combine #rom 
		\combine \path #0.0 #'((moveto 0 -1.4)(lineto 0 -1.4)) %solo amplia imagen
			\postscript 
#(string-append " 
/ycero -0.4 def
/xcero {1.4 "(number->string xceroadd)" add} def
/largoflecha "(number->string largoflechax)" def
/segmentado "(if segmentadox "true" "false" ) " def
/arrowhead {% stack: s x1 y1  , current point: x0 y0
gsave
	currentpoint		% s x1 y1 x0 y0
	4  2 roll exch 		% s x0 y0 y1 x1
	4 -1 roll exch 		% s y0 y1 x0 x1
	sub 3 1 roll		% s x0-x1 y0 y1
	sub exch			% s y0-y1 x0-x1
	atan rotate		% s	% rotate over arctan((y0-y1)/(x0-x1))
	dup scale				% scale by factor s
	-7  3 rlineto
	 2 -3 rlineto
	-2 -3 rlineto
	closepath fill % fill arrowhead
grestore
newpath
} def

0.12 setlinewidth 		%ancho de la linea
segmentado {[0.42 0.35] 0 setdash} if %[lleno vacio] inicio setdash configurar segmentado
%curva
xcero ycero moveto

xcero ycero
xcero largoflecha 2 div add 	largoflecha -0.6 mul 
xcero largoflecha add -0.4 add		ycero -0.3 add
curveto stroke

%cabeza de flecha
xcero largoflecha add ycero moveto

0.16 xcero largoflecha 2 div add
largoflecha -0.5 mul
arrowhead
")
     #}))


<<
\new Staff \relative c' {c2 d d g  c,1 \bar "|."
	}
 \new Lyrics \lyricmode { 
	I2 \markup \harm-arrow #9.3 #0 ##t Vs II \markup \harm-arrow #5 #0 ##f V  I1}
>>